Air travel has long been, and continues to be, a safe mode of transportation. Nonetheless, substantial effort continues to be expended to develop flight systems and human-factors practices that even further improve aircraft flight safety. Some examples of these flight systems include flight management systems, global navigation satellite systems, differential global positioning systems, air data computers, instrument landing systems, satellite landing systems, traffic alert and collision avoidance systems, weather avoidance systems, thrust management systems, flight control surface systems, and flight control computers, just to name a few.
Despite good flight system design and improved human-factors practices, there is a continuous desire to provide further flight safety improvements. One particular aspect that is presently undergoing significant improvement is in the area of obstacle avoidance. It is generally understood that improving aircraft flight crew situational awareness during flight operations, ground operations, and landing operations, will likely improve the ability of a flight crew to avoid obstacles.
During flight operations, flight crews make every effort to consistently survey the region around the aircraft. However, aircraft structures, such as the wings and the aft lower fuselage, may block large regions of airspace from view. Moreover, at times the cockpit workload can possibly detract the flight crew from visual scanning. To enhance situational awareness during crowded air traffic and/or low visibility flight operations, many aircraft are equipped with a Traffic Alert and Collision Avoidance System (TCAS) and an Automatic Dependent Surveillance-Broadcast System (ADS-B). Although the TCAS/ADS-B does provide significant improvements to situational awareness, the burden remains on the pilots of TCAS-equipped aircraft to avoid another aircraft.
Existing TCAS systems record incoming messages from nearby traffic aircraft received by the ADS-B transponder and assembles these messages into reports. The ADS-B specification in RTCA/DO-242A (Minimum Aviation System Performance Standard) describes the intent elements used for surveillance applications that estimate the flight trajectory of intruder traffic aircraft. The ADS-B mandate requires aircraft to broadcast a state vector only, the target state (TS) intent broadcast is optional, and the trajectory change (TC) message is not included in the mandate. The elements in all the three reports are considered as intent data.
Even after the year 2020 when ADS-B will be mandated on most aircraft, there will be many airspace users that will be not equipped, non-cooperative or non-participating targets. If the host aircraft wants to fly in those areas, it will need a way to track and avoid those non-ADS-B aircraft. With the integration of RADAR target data into the on-board computer and broadcasted ADS-B information available every second, any “data dropouts” (i.e., those aircraft not providing ADS-B information) would be noted as attention items on the ownship flight deck displays.
Hence, there is a need for a system and method of improving aircraft flight crew situational awareness during flight operations. Particularly, there is a need for a system and method for displaying degraded intruder traffic data on an aircraft display. More particularly, there is a need for a system and method to detect and alert the pilot about an aircraft within the specified close range of host aircraft that has its TCAS/ADS-B critical/non-critical intent data dropped over a specified amount of time. The present disclosure addresses at least this need.